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[JavaScript] 特定の文字数をカウント

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文字列中に特定の文字が何回出現するかを数える自作関数です。正規表現に変数を使えるよう、RegExp を利用します。

yotsuba_s.jpg サンプルコード

JavaScript
var all = "aaa\naaaa\nbbc";
alert(str_count(all, "\n")); // 2
alert(str_count(all, "aa")); // 3

// all の中に part が出現する回数を取得
function str_count(all, part) {
    return (all.match(new RegExp(part, "g")) || []).length;
}

yotsuba_s.jpg デモはこちら

http://jsfiddle.net/yasumodev/fLbw63cn/1/

(・o・ゞ いじょー。

yasumodev
「長い旅行に必要なのは大きなカバンじゃなく、口ずさめる一つの歌さ」スナフキン
https://twitter.com/yasumodev
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